Short answer: both are discontinued, so this only matters if you are buying used. Used, the JBL 4645C is the better pick: it ranks #25 of 143 subwoofers by sound quality (rated 4.4/5), against #34 (rated 4.3/5) for the Chase Home Theater SS18.1. If you want one new, the JTR Speakers Orbit Shifter PRO ranks #1 at $4,499.
Buy the JBL 4645C only if you find one used in good condition; both are discontinued, and it is the better rated of the two. For a new speaker, start with the JTR Speakers Orbit Shifter PRO instead.
Want more options? Browse the full Subwoofers rankings.
Prices on this page were last checked November 7, 2026 at 7:34 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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Specifications Side By Side
| Chase Home Theater SS18.1 | JBL 4645C | |
|---|---|---|
| Price | $2,499 Passive, Discontinued | $4,999 Passive, Discontinued |
| Ranked | #34 of 143 in Large Home Subwoofers (Over 75 lbs) | #25 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported, front |
| Passive | Yes | Yes |
| Output SPL at 12.5 Hz | 92.8 dB | - |
| Output SPL at 15 Hz | 97.2 dB | - |
| Output SPL at 20 Hz | 101.3 dB | 98.9 dB |
| Output SPL at 25 Hz | 106.0 dB | 114.0 dB |
| Output SPL at 31.5 Hz | 111.6 dB | 118.7 dB |
| Output SPL at 40 Hz | 118.2 dB | 122.0 dB |
| Output SPL at 50 Hz | 123.6 dB | 123.7 dB |
| Output SPL at 63 Hz | 128.1 dB | 129.7 dB |
| Output SPL at 80 Hz | 130.8 dB | 133.9 dB |
| Output SPL at 100 Hz | 132.6 dB | 135.1 dB |
| Output SPL at 125 Hz | 133.7 dB | 135.8 dB |
| CEA-2010-A Average (40-80Hz) | 125.2 dB | 127.3 dB |
| Dimensions | 22”H x 24”W x 22”D (558.8 x 609.6 x 558.8 mm) | 39.7”H x 26.5”W x 17.7”D (1009.6 x 673.1 x 450.8 mm) |
| Measurement Source | Data-bass | Data-bass |
| Weight | 89.9 lbs (40.8 kg) | 138 lbs (62.6 kg) |
| Drivers | 18” (457mm) driver | 18” (457mm) driver |
| Country | USA | United States |
| Warranty | - | 5/3/2 |
| Cabinet Color | - | black |
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